#include <iostream>
#include <queue>
#include <cstring>
using namespace std;
const int N = 1e5 + 5, M = 2 * N;
int h[N], e[M], ne[M], idx;
void add(int a, int b)
{
    e[idx] = b; ne[idx] = h[a]; h[a] = idx++;
}
int n, m;
int color[N];

bool dfs(int u, int c)
{
    color[u] = c;
    for(int i = h[u]; i != -1; i = ne[i])
    {
        int j = e[i];
        if(!color[j])
        {
            if(!dfs(j, 3 - c))
                return false;
        }
        else if(color[j] == c)
            return false;
    }
    return true;
}

int main()
{
    memset(h, -1, sizeof h);
    cin >> n >> m;
    while(m--)
    {
        int a, b; cin >> a >> b;
        add(a, b); add(b, a);
    }
    
    bool flag = true;
    for(int i = 1; i <= n; ++i)
    {
        if(!color[i])
        {
            if(!dfs(i, 1))
            {
                flag = false;
                break;
            }
        }
    }
    
    if(flag) cout << "Yes";
    else cout << "No";
    
    return 0;
}